Air spring assembly apparatus

ABSTRACT

A chuck member holds the end fitting of the air spring and inserts the fitting in the open end of a tubular sleeve of the spring. A housing is provided for axial movement toward and away from the chuck. An annular segmental clamping member is located in an opening in the housing and the segments are moved radially inward for positioning and crimping a ring member of the spring in response to controlled axial movement of the housing. Axial movement of the segments for positioning the ring member and inserting the end fitting may be provided by piston and cylinder assemblies. A crimping chamber in the housing is utilized to move the housing and actuate cam means engageable with the segments to provide the desired radial force which is applied by the segments during positioning and crimping of the ring member.

This invention relates generally, as indicated, to the assembly of airsprings and particularly to the insertion of an end fitting in one endof a tubular sleeve member, positioning and crimping a ring memberaround the tubular member and over the end fitting. Still moreparticularly the invention relates to a method and apparatus which isprecise and fast in operation and is adaptable for automatic operation.

According to one aspect of the invention there is provided a method ofassembling a tubular member with an end fitting inserted in an open endof the tubular member and held in place by crimping a ring member aroundthe open end of the tubular member over said fitting comprising placingsaid ring member over the end of said tubular member, inserting said endfitting into the open end of said tubular member, contracting segmentsof an annular segmental clamping member to positions on the surface ofsaid tubular member for clamping engagement with said ring member,increasing the clamping force exerted by said clamping member to crimpsaid ring member and thereafter radially expanding said segments out ofcontact with said ring member.

According to another aspect of the invention there is provided anapparatus for radially compressing an article comprising a housinghaving an opening, an annular segmental clamping member located withinsaid opening in the assembled condition and having a series of segmentsspaced around an axis and movable radially into compressing engagementwith the article, each of said segments being attached to a fingermember positioned in said opening and pivotally mounted on a supportingmember for swinging movement between a contracted assembled position ofsaid segmental member and an expanded position spaced outwardly fromsaid assembled position, means for moving said housing in an axialdirection, means interposed between each said finger member and saidhousing for swinging said finger member and the attached segmentradially inwardly toward the assembled position of said segmental memberin response to movement of said housing in a first axial directiontoward a front end of said apparatus for contracting the segments intocompressing engagement with the article and means connected to each saidfinger member for swinging the segments outwardly away from theassembled position of said segmental member in response to movement ofsaid housing in a second axial direction opposite to said first axialdirection for expanding the segments after radial compression of thearticle.

To acquaint persons skilled in the arts most closely related to thepresent invention, a certain preferred embodiment thereof illustrating abest mode now contemplated for putting the invention into practice isdescribed herein by and with reference to the annexed drawings forming apart of the specification. The embodiment shown and described herein isillustrative and as will become apparent to those skilled in these artscan be modified in numerous ways within the spirit and scope of theinvention defined in the claims hereof.

In the drawings:

FIG. 1 is a side elevation of the apparatus embodying the invention withparts being broken away.

FIG. 2 is an end view taken along the line 2--2 of FIG. 1 with partsbeing broken away.

FIG. 3 is an enlarged elevation partly in section of the spindle baseassembly shown in FIG. 1.

FIG. 4 is an enlarged end view of the end fitting chuck with the endfitting removed.

FIGS. 5, 6, 7 and 8 are elevations partly in sections like FIG. 3showing other positions of the parts of the spindle base assembly duringthe assembly process.

Referring to FIGS. 1 and 2, an air spring assembly apparatus 10 is shownpositioned with a front end at one side of a stand 12 for supporting acylindrical tubular member such as an air spring sleeve 14 of reinforcedrubberlike material. The apparatus 10, shown and described hereinafter,is for processing one end 16 of the sleeve 14 and an identical apparatusmay be positioned at the other end (not shown) of the air spring sleevefor processing that end in a manner similar to that described for theend 16. The apparatus for processing the other end of the air springsleeve 14 is positioned the same distance from a center plane A--A ofthe stand 12 as the apparatus 10 shown in FIGS. 1, 2 and 3.

The air spring assembly apparatus 10 has a main frame 18 with legs 20connected by horizontal end members 22 and horizontal side members 24.Tracks 26 are mounted on the inside of the upper side members 24 forsupporting and guiding rollers 28 rotatably mounted on side supports 30extending downwardly from a base member 32 of a spindle base 34. Thespindle base 34 is movable toward the front of the apparatus 10 to anoperating position, as shown in FIG. 1, and away from the front of theapparatus to an open position spaced from the stand 12 so that theassembled air spring may be removed from the stand and another airspring sleeve 14 placed on the stand for processing.

An intermediate frame 36 is also slidably mounted on the tracks 26 ofthe main frame 18 by rollers (not shown) which are rotatably mounted onside supports 38 connected to a bottom plate 40. The position of theintermediate frame 36 between the end members 22 is adjustably set bysuitable means such as a screw 42 held rotatably in bearing blocks 44mounted on end members and being threadedly engaged in a threaded sleeve46 mounted on the bottom plate 40 of the intermediate frame. A crank 48mounted on the end of the screw 42 may be turned to move theintermediate frame 36 along the tracks 26. A lock 50 may be provided toprevent turning of the screw 42 after the position of the intermediateframe 36 has been set.

A piston and cylinder assembly 52 is mounted on the bottom plate 40 ofthe intermediate frame 36 and has a piston rod 54 connected to a bracket56 fastened to the base member 32 of the spindle base 34 for moving thespindle base along the tracks 26. The distance the spindle base 34 ismoved is controlled by stop members 58 mounted on the base member 32 andengageable with stops 60 mounted on brackets 62 fastened to the bottomplate 40 of the intermediate frame 36. Shock absorbers 64 may also bemounted on the brackets 62 for engagement with the stop members 58 tocushion the stoppage of the spindle base 34.

Referring to FIGS. 2 and 3, the spindle base 34 has an end member 66 andside members 68 mounted on the base member 32. A center shaft 70 ismounted on the end member 66 and extends toward the front end of theapparatus 10. A chuck 72 may be mounted on the front end of the shaft 70for holding an end fitting 74 for insertion in the end 16 of the airspring sleeve 14 and gripping of the fitting during the assemblyprocess.

Slidably mounted on the center shaft 70 is a finger base assembly 76having a radially inner cylindrical member 78 positioned around theshaft. An annular piston plate 80 extends radially outward from theinner cylindrical member 78 and an outer cylindrical member 82 extendsaxially from the piston plate. The inner cylindrical member 78 has aninner diameter substantially the same as the outer diameter of thecenter shaft 70 over the positions where the finger base assembly 76 isaxially movable. Radially outward of the finger base assembly 76 is ahousing such as crimping drum 84 which has an annular cylinder end plate86 with a cylindrical radially inner surface 88 slidably mounted on theouter surface of the inner cylindrical member 78 of the finger baseassembly. An outer cylindrical shell 90 extends axially from the endplate 86 and is slidably mounted on the radially outer cylindricalmember 82 of the finger base assembly 76 to form with the radially innercylindrical member 78 a crimping chamber 92. The crimping chamber 92 isconnected to a suitable source of air pressure and vacuum by ports inthe chamber (not shown) and conduits leading to vacuum pumps and aircompressors.

The shell 90 has a front extension 94 providing an opening 95 in whichan annular segmental clamping member 96 is located. The segmentalclamping member 96 has a series of segments 98 spaced around an axisB--B. The segments 98 are attached to finger members such as arms 100positioned in the opening 95 and pivotally mounted on a supportingmember such as the inner cylindrical member 78 which has a ring 102 withslots for receiving the ends of the arms 100 and holes through whichpivot pins 104 may be inserted through the ends of the arms. The arms100 provide for swinging movement of the segments 98 between thecontracted assembled position, shown in FIGS. 2 and 3, to an expandedposition spaced outwardly from the assembled position, shown in FIGS. 5and 6. Cam members 106 are mounted on the radially outer surfaces of thearms 100 and have cam surfaces 108 engageable with cam rollers 110rotatably supported in brackets 112 mounted on the shell front extension94 at circumferentially spaced positions within the opening 95. As shownin FIG. 3, the cam surfaces 108 have dwell portions 114 spaced apredetermined distance from the axis B--B and clamping portions 116spaced a greater predetermined distance from the axis.

Resilient means are provided to radially expand the segments 98 when thecam rollers 110 are moved axially away from the front end of theapparatus and in this embodiment includes coil springs 118 betweenblocks 120 on each of the arms 100 and an annular plate 122 fastened tothe inner cylindrical member 78 of the finger base assembly 76.

During the operation of this apparatus it is desirable to limit themovement of the end plate 86 relative to the inner cylindrical member 78and for this purpose resilient means such as springs 124 mounted inhousings 126 are fastened to the inner cylindrical member of the fingerbase assembly 76 at spaced-apart circumferential positions and havespring ends 128 for contacting the end plate to resist the movement ofthe plate and maintain the cam rollers 110 in engagement with the dwellportions 114 of the cam surfaces 108.

At least one end member piston and cylinder assembly connects theannular piston plate 80 of the finger base assembly 76 and the endmember 66 of the spindle base 34. In the present embodiment, two pistonand cylinder assemblies 130 are positioned 180 degrees apart around thecenter shaft 70 with a cylinder of each of the assemblies beingpivotally mounted on the piston plate 80 and a piston rod 132 of each ofthe assemblies being pivotally mounted on a pin 134 fastened to the endmember 66. To prevent rotation of the shell 90 around the center shaft70, a centering key 136 may be provided extending through the basemember 32 into a slot or keyway in the shell.

Referring to FIGS. 3 and 4, the chuck 72 for holding the end fitting 74is fastened to the front end of the center shaft 70 by screws 138extending through holes 140 in the chuck and threaded in correspondingholes in the center shaft. An opening 142 is provided for protrudingparts of the end fitting 74 and a sealing gasket member 144 is providedfor engagement with the flat surface of the end fitting for enclosing aspace 146 between the chuck 72 and the end fitting. An aperture 148 inthe chuck 72 is in communication with a passage 150 through the centershaft 70 which may be connected to a source of vacuum to hold the endfitting 74 in the chuck. With other forms of end fittings 74 the chuck72 may have a different face so that the vacuum chamber or chambers inthe space 146 conform with the flat surfaces of the end fitting 74.

As shown in FIGS. 1 and 2, proximity switches 152 may be provided on thespindle base 34 for registering the various axially spaced positions ofthe shell 90 of the crimping drum 84. Also frame switch means such asproximity switches 154 may be fastened to the intermediate frame 36 forindicating when the spindle base 34 is in the operating or openposition. In this embodiment, the piston and cylinder assemblies 52,130and the crimping chamber 92 are activated by air pressure which providesa faster and less expensive operation than with hydraulic actuatedpistons and cylinders. The electrical, air and vacuum services for thespindle base 34 may be provided through a flexible connection 156, shownwith parts broken away in FIGS. 1 and 2.

Where desirable, a failsafe expansion of the segments 98 may be obtainedby rollers 158 mounted on the brackets 112 attached to the inner surfaceof the shell 90 in the opening 95 for engagement with the surfaces ofthe blocks 120 fastened to the arms 100. With this construction, therollers 158 are positioned for engagement with the blocks 120 in theevent the springs 118 do not expand the segments 98 by swinging the arms100 radially outward.

In operation, the spindle base 34 is initially in a retracted positionwith the rear stop member 58 of the spindle base in contact with therear stop 60 on the bracket 62 of the intermediate frame 36. To move thespindle base 34 from the position shown in FIG. 1 to this retractedposition, the operator directs air into the piston and cylinder assembly52 causing the piston rod 54 to move to the right as shown in FIG. 1.With the spindle base 34 in the retracted position, a vacuum is appliedto the crimping chamber 92 causing the end plate 86 of the finger baseassembly 76 to move to the right, as shown in FIG. 5, into a positionclosely adjacent the piston plate 80 of the crimping drum 84. As thecrimping drum 84 moves to the right, as shown in FIG. 5, the cam rollers110 roll off of the cam members 106 and the springs 118 cause the arms100 to move radially outward carrying the segments 98 to an expandedposition. In the event that the springs 118 do not provide sufficientforce to move the arms 100 radially outward, the rollers 158 willcontact the blocks 120 to insure that this radial movement does occur.

With the spindle base 34 in the retracted position and the segments 98expanded, the end fitting 74 may be placed in the chuck 72 and a vacuumcommunicated to the space 146 through the passage 150 in the centershaft 70. The placing of the end fitting 74 may be done manually or withsuitable automatic handling equipment.

At this time the spring sleeve 14 may be placed on the stand 12 and aring member such as ring 160 is placed over the end 16 of the sleeve ata position which may be plus or minus 0.9 inches from a predeterminedinitial position. The ring 160 may be of aluminum or of other materialswhich can be crimped by radial compression. At the same time that thering 160 is placed over the end 16 of the sleeve 14 another ring (notshown) may be placed over the other end of the sleeve for processing bya similar air spring assembly apparatus (not shown) at the opposite sideof the stand 12. The apparatus also has a chuck for holding an endfitting to be inserted in the other end of the sleeve.

After the ring 160 has been placed over the end 16 of the sleeve 14 andthe end fitting 74 placed in the chuck 72, the spindle base 34 is movedto the left, as shown in FIG. 1, to the operating position with theforward stop member 58 on the spindle base in contact with the forwardstop 60 on the intermediate frame 36. During this forward movement theend fitting 74 is pushed into the open end 16 of the sleeve 14, as shownin FIG. 6. Simultaneously the chuck in the other air spring assemblyapparatus 10 at the other end of the air spring sleeve 14 pushes the endfitting at that end into the open end of the sleeve so that the axialpressure at one end of the sleeve is counteracted by the axial pressureat the other end. This movement of the spindle base 34 actuates theframe proximity switch 154 indicating to the operator that this movementhas occurred. The actuation of the frame proximity switch also may beused to start an automatic process for positioning and crimping the ring160.

In order to position the ring 160 on the end 16 of the sleeve 14, air isadmitted to the piston and cylinder assembly 130 between the end member66 of the spindle base 34 and the piston plate 80 of the finger baseassembly 76. This may be done before the end fitting 74 is positioned inthe end of the sleeve 14, as shown in FIG. 5, or after the end fittingis positioned, as shown in FIG. 6. The piston rod 132 will be extendedand move the finger base assembly 76 and the crimping drum 84 to theleft, as shown in FIGS. 5 and 6. Then when the arms 100 are movedradially inward the segments 98 will engage the surface of the sleeve 14at a position on the other side of the ring 160 from the end 16 of thesleeve 14, as shown in FIG. 7. The position of the spindle base 34 inFIG. 6 is indicated by one of the drum proximity switches 152 whichprovides a signal in the automatic process for communicating lowpressure air to the crimping chamber 92 causing the end plate 86 to moveto the left, as shown in FIG. 7, and engage the springs 124 which limitthe movement so that the cam rollers 110 only engage the dwell portions114 of the cam surfaces 108 and the arms 100 are moved radially inwardcarrying the segments 98 into loose engagement with the surface of thesleeve 14 as shown in FIG. 7. In this position the segments 98 may ormay not engage the ring 160 but are in a position to engage the ringwhen moved to the right as shown in FIG. 7.

Following the radially inward movement of the arms 100 and the segments98, which movement is indicated by one of the drum proximity switches152, air pressure is communicated to the piston and cylinder assemblies130 causing the piston plate 80 to move to the right toward the endmember 66 of the spindle base 34 and pulling the ring 160 to the right,as shown in FIG. 7, to a predetermined final position over the endfitting 74, as shown in FIG. 8. This is done while the low pressure airof from zero to about fifteen pounds per square inch is in communicationwith the crimping chamber 92 so that the cam rollers 110 remain inengagement with the dwell portions 114 of the cam surfaces 108. Afterthe segments 98 have moved the ring 160 to the predetermined finalposition around the end fitting 74, the position of the crimping drum 84will be indicated by one of the drum proximity switches 152 and highpressure air may then be communicated to the crimping chamber 92. Thehigh pressure air may be from about 50 to 150 pounds per square inch.

With the admission of the high pressure air, the end plate 86 of thecrimping drum 84 will be moved to the left, as shown in FIG. 8, to theposition shown in FIG. 3 with the spring 124 fully compressed and thecam rollers 110 in engagement with the clamping portions 116 of the camsurfaces 108. This causes the segments 98 to move radially inward intoclamping engagement with the ring 160 causing crimping of the ring tosecure the end 16 of the sleeve 14 against the end fitting 74, as shownin FIG. 3. This position of the drum is also indicated by one of thedrum proximity switches 152 which may actuate the controls for automaticoperation by terminating the communication of high pressure air to thecrimping chamber 92 and opening the chamber to a vacuum source causingthe end plate 86 to move to the right, as shown in FIG. 3, toward thepiston plate 80 to the position shown in FIG. 5 with the segments 98expanded. The position of the drum 84 shown in FIG. 3 is also indicatedby one of the proximity switches 152. At the same time the vacuum iscommunicated to the crimping chamber 92 communication of the vacuum tothe chuck 72 is discontinued.

After the segments 98 are expanded and the communication of vacuum tothe chuck 72 is discontinued, air pressure is communicated to the pistonand cylinder assembly 52 on the intermediate frame 36 for retracting thespindle base 34 to facilitate removal of the assembled air spring sleevefrom the stand 12 manually or by other conveying equipment.

Different length air spring sleeves 14 may be assembled with thisapparatus by moving the intermediate frame 36 toward the front or rearof the apparatus by turning the crank 48, as shown in FIG. 1. Alsodifferent diameter sleeves 14 with different end fittings 74 may beprocessed by providing different size chucks 72 and changing thesegments 98 to provide a segmental clamping member 96 of a differentinner diameter.

While a certain representative embodiment and details have been shownfor the purpose of illustrating the invention, it will be apparent tothose skilled in the art that various changes and modifications may bemade therein without departing from the spirit or scope of theinvention.

What is claimed is:
 1. Apparatus for radially compressing an articlecomprising a housing having an opening, an annular segmental clampingmember located within said opening in the assembled condition and havinga series of segments spaced around an axis and movable radially intocompressing engagement with the article, each of said segments beingattached to a finger member positioned in said opening and pivotallymounted on a supporting member for swinging movement between acontracted assembled position of said segmental member and an expandedposition spaced outwardly from said assembled position, means for movingsaid housing in an axial direction, means interposed between each saidfinger member and said housing for swinging said finger member and theattached segment radially inwardly toward the assembled position of saidsegmental member in response to movement of said housing in a firstaxial direction toward a front end of said apparatus for contracting thesegments into compressing engagement with the article and meansconnected to each said finger member for swinging the segments outwardlyaway from the assembled position of said segmental member in response tomovement of said housing in a second axial direction opposite to saidfirst axial direction for expanding the segments after radialcompression of the article.
 2. Apparatus in accordance with claim 1wherein said means interposed between each said finger member and saidhousing includes a cam member mounted on the radially outer surface ofeach said finger member and having a cam surface engageable with a camroller mounted on said housing within said opening.
 3. Apparatus inaccordance with claim 2 wherein said means for swinging segmentsoutwardly away from the assembled position of said segmental memberincludes spring means between each said finger member and saidsupporting member.
 4. Apparatus in accordance with claim 2 wherein saidsupporting member includes a finger base assembly comprising a radiallyinner cylindrical member slidably mounted on a center shaft with thefinger members attached to said segments being pivotally mounted on saidradially inner cylindrical member at circumferentially spaced-apartpositions around said inner cylindrical member.
 5. Apparatus inaccordance with claim 4 wherein said finger base assembly includes anannular piston plate extending radially outward from said cylindricalmember and an outer cylindrical member extending axially from saidpiston plate and said housing includes a crimping drum having a radiallyextending annular end plate mounted slidably on said radially innercylindrical member of said finger base assembly, said crimping drumhaving an outer cylindrical shell slidably mounted on said radiallyouter cylindrical member of said finger base assembly to form with saidradially inner cylindrical member a crimping chamber for moving saidcrimping drum axially upon communication of air pressure or vacuum withsaid chamber, said outer shell extending axially toward said front endof said apparatus from said end plate and having a reinforcing ring atthe front edge of said shell.
 6. Apparatus in accordance with claim 3wherein each said finger member has a block member extending radiallyoutward engageable with a roller mounted on said housing inside saidopening upon movement of said housing in said second axial direction topositively swing said segments radially outward.
 7. Apparatus inaccordance with claim 1 wherein said article is a ring member locatedaround a tubular member having an end fitting inserted in an open end ofsaid tubular member for crimping of said ring member around said openend and over said fitting, said apparatus including a chuck membermounted on the front end of said apparatus for holding said end fittingin position for insertion into said tubular member, said chuck memberbeing in communication with a source of vacuum and having sealingmembers in sealing engagement with portions of said end fitting defininga vacuum chamber for holding the end fitting in said chuck member. 8.Apparatus in accordance with claim 7 wherein a center shaft is mountedon an end member of a spindle base having a base member and sidemembers, said chuck member being mounted on the front end of said centershaft for holding said end fitting in position for insertion into saidtubular member, and said chuck member being in communication with saidsource of vacuum through a passage in said center shaft.
 9. Apparatus inaccordance with claim 4 wherein said article is a ring member locatedaround a tubular member having an end fitting inserted in an open end ofsaid tubular member for crimping said ring member around said open endand over said fitting, said apparatus including means to adjust theposition of said finger base assembly in an axial direction to axiallymove said clamping segments to positions on the surface of said tubularmember located on the opposite side of said ring member from the end ofsaid tubular member and for axially moving said segments over said endfitting into position for clamping of said ring member by said segments.10. Apparatus in accordance with claim 8 wherein at least one end memberpiston and cylinder assembly connects said end member of said spindlebase and said piston plate of said finger base assembly for axiallymoving said piston plate toward and away from said end member toposition said clamping segments on the surface of said tubular member ata location on the opposite side of said ring member from the end of saidtubular member and for axially moving said segments from that locationtoward said open end of said tubular member to position said ring memberover said end fitting.
 11. Apparatus in accordance with claim 9 whereineach said cam surface has a dwell portion for engagement by said camroller while positioning said ring member over said end fitting and aclamping portion for engagement by said cam roller to crimp said ringmember, said apparatus further including air pressure supply means incommunication with said crimping chamber for supplying low pressure airto said chamber for moving said cylinder end plate of said drum aninitial distance away from said piston plate of said finger baseassembly causing said cam rollers to engage said dwell portion of saidcam surface of each said cam member and thereafter to provide highpressure air to move said cylinder end plate a further distance awayfrom said piston plate causing said cam rollers to engage said clampingportion of each said cam surface.
 12. Apparatus in accordance with claim11 including spring means mounted on said radially inner cylindricalmember of said finger base assembly for engagement with said cylinderend plate of said crimping drum to hold said cam rollers in engagementwith the dwell portion of said cam surface when low pressure air is incommunication with said crimping chamber and said spring means resistingmovement of said end plate with less force than the force exerted byhigh pressure air in said crimping chamber permitting movement of saidcam rollers into engagement with the clamping portion of each said camsurface.
 13. Apparatus in accordance with claim 7 including means forholding said tubular member with said open end spaced from said frontend of said apparatus and means to move said end fitting axially towardsaid front end of said apparatus to insert said fitting in said open endof said tubular member.
 14. Apparatus in accordance with claim 13wherein said housing, said supporting member and said chuck member aremounted on a base member slidably mounted on a supporting frame foraxial movement of said base member.
 15. Apparatus in accordance withclaim 14 wherein said supporting frame includes an intermediate framemember connected to said base member, said intermediate frame memberbeing adjustably mounted on said supporting frame, a piston and cylinderassembly mounted on said intermediate frame member and having a pistonrod connected to said base member axially of said apparatus. 16.Apparatus in accordance with claim 15 wherein said intermediate framemember has stop means engageable with stop members on said base memberto limit movement of said base member during installation of the endfitting in said tubular member and during the removal of said chuckmember from said end fitting after crimping of said ring member and saidintermediate frame member having position adjusting means for movingsaid intermediate frame member axially to position said base member forinserting the end fitting in different length tubular members. 17.Apparatus in accordance with claim 16 wherein said intermediate framehas shock absorbers engageable with said stop members mounted on saidbase member.
 18. Apparatus in accordance with claim 9 including drumswitch means positioned between said crimping drum and said spindle baseto indicate the position of said drum for determining when each step ofthe process performed by this apparatus has been completed. 19.Apparatus in accordance with claim 15 wherein frame switch means arepositioned between said intermediate frame and said base member toindicate the position of said base member for providing the operator ofsaid apparatus with information as to when the base member is in theoperating position at the front end of the apparatus and in theretracted position at the other end of the apparatus.